[cxx-abi-dev] IEEE 754r half-precision fp mangling?

[Mark Mitchell]

scott douglass wrote:

>> I would suggest you just use "D".  I.e. save "E" for End as in most
>> other parts of the BNF.
> 
> Thanks. I'm happy to use 'D<letter>' if there's already a precedent.

I don't see any precedent there -- but I think we could do that.

> If 'Dh' is available, I change my proposal to:
> 
> <type> ::= Dh # half-precision floating point (16bit)

Here is another possible trick that we could use for both DFP and 
half-precision float...  Since we have:

		 ::= u <source-name>	# vendor extended type

and since a source name always starts with a decimal integer, we already 
have a piece of the encoding space reserved, given by the regular 
expression:

    u[a-zA-Z].+

So, we could use "uh" for half-precision float.  That's the same number 
of characters and avoids using any new encoding space?

-- 
Mark Mitchell
CodeSourcery
mark at codesourcery.com
(650) 331-3385 x713